22 April 2013

Mike McDonough: Opioid consensus

DRUG addiction, like other diseases has a multifactorial aetiology — it is not the result of genetic predisposition or family environment alone, but it does require drug exposure.

The opportunities to acquire a drug of addiction and maintain the supply of that drug are one of the important aetiological factors that determine (and prevent) drug addiction.

During a recent heroin epidemic, increased availability of heroin (making it cheaper) was clearly associated with increased addiction and related harms including a dramatic increase in heroin-related deaths. Conversely, when supply diminished, so too did the heroin epidemic.

Hence, the relationship between drug supply, drug addiction and drug-related harm is a fundamental one.

In the past decade, the rate of pharmaceutical opioid analgesic prescribing has dramatically increased in Australia and increased recognition of opioid-related harm is now evident, as it has been for nearly two decades in North America. It was reported in the US that opioid analgesic-related deaths now exceed the annual motor vehicle mortality rate.

What is most concerning is that opioid prescribing has escalated despite minimal evidence for its use in non-malignant pain, and beyond various clinical guidelines and despite increasing calls for caution with opioids.

Long-term opioid prescribing carries even more significant risks of adverse effects. Recent evidence indicates that patients taking doses of 200 mg morphine-equivalent daily for prolonged periods have an appreciable increased risk for opioid-related death and also that interventions to limit the dose prescribed (eg, ranging between 120 mg–200 mg daily maximum) have been associated with reductions in opioid mortality.

Last year in Melbourne, at a forum on S8 opioid prescribing, it was acknowledged that we have a professional responsibility for action in regards to opioid prescribing, a sentiment shared by physicians elsewhere.

Medical consensus about opioid prescribing practices is likely to be both more reasonable and effective than calls for penalties.

Like most professions, the medical profession is a self-regulating body, and it is preferable to have the profession as a whole establish a consensus about opioid prescribing practices rather than waiting for “others to act”, such as by increasing regulation and/or penalties.

Any prescription drug epidemic, by its nature, requires prescription/prescribing doctor participation, with iatrogenesis recognised as a significant and potentially preventable component of this epidemic.

Currently, it appears that because a lot of doctors are prescribing high doses of opioids and for protracted periods, this practice may have become somewhat normative. Adopting a daily dose threshold of 200 mg morphine-equivalent would seem a reasonable place to start in view of the evidence.

If accepted by consensus, this could send a clear message to the profession that prescribing at this dose or above for prolonged periods is associated with increased mortality risk. That might also promote additional caution by prescribers on any further dose escalation, consideration for specialist review and may even have a public health benefit by discouraging prolonged and high-dose prescribing.

The dosage threshold may also remind prescribers that continuing such treatment carries considerable risk and should prompt a re-evaluation of the risk–benefit ratio. Any continued prescribing should, as always, incorporate a continued focus on the monitoring of both safety and efficacy of any opioid medication.

It is reasonable to assert that the prescription opioid epidemic is largely an iatrogenic problem and is therefore preventable. The structure of our health system may be implicated in the prescription opioid epidemic as prescribers may be unaware that patients they are treating with opioids are attending one or more other doctors for similar prescriptions.

In many states, an opioid permit system operates to discourage multiple opioid prescribers. Currently, in Tasmania, real-time recording of S8 prescription drugs has commenced and eventually may greatly help reduce multiple opioid prescribing.

There have been many calls for action on opioid prescribing consequences and questions raised about physician/prescriber responsibility, but I believe in a profession-wide consensus. In the meantime, we still have the principle primum non nocere.

Associate Professor Mike McDonough is the head the addiction medicine and toxicology unit with Western Health in Melbourne.

5 thoughts on “Mike McDonough: Opioid consensus”

Why is it that a person admitted to ED with a sports injury (myself) is administered opiods but a person (myself) presenting with migraine and significantly more pain is administered NSAIDS with no pain relief and left to suffer while the attending doctor cites fear of opioid addiction. Why have migraine sufferers been singled out as people not requiring opiod medication?

I believe that is because opioids are not recommended in the treatment of migraine, due to other drugs having better efficacy and mechanisms of action, and the high risk of rebound headaches when opioids are used. I counsel all my patients against using opioids for migraine.

In the 1960s, students and young doctors were well instructed about the addictive properties of opiates and it was professionally unacceptable for a doctor to prescribe opioids for chronic pain other than in terminal malignancy. The wheel has gradually turned and perhaps palliative care specialists might have wittingly or unwittingly contributed to the current fashion of prescribing opioids for non-malignant conditions. The advent of reasonably well absorbed oral opiates probably aided this trend. I agree that it is up to the profession to turn the wheel back.

I would suggest that the A & E Doctors be the first to be educated on opioid use. They seem to “dole them out like lollies”. I have had another example today with one of my patients given Endone when a well chosen anti-inflammatory and less potent analgesic would have been sufficient.

In reply to William Warr, in 1979 we would hand out Nembudeine (paracetamol, codeine and a barbiturate) as the “get out of my Casualty Dept” drug.
Then it was Pethidine used for everyone (I have spent years full time in Emergency Departments)
Now it’s Endone. I agree that far too much oxycontin is passed out through Emergency Departments, with no regard to the possibility that other analgesics might really work better. However, we don’t see anywhere near as many old adults with ruptured gastric ulcers without those NSAIDS.